The use of ceramic gas filter elements in high temperature applications is well known. Such filters elements have been relatively heavy and have necessitated the use of massive structural members to support them properly at high temperatures within a filter tank. It has recently been found that the weight of the filter elements can be greatly reduced by constructing the elements of a ceramic filled skeletal base formed of matted ceramic fibers. However, it has still been necessary to utilize heavy structural members to support such filter elements inasmuch as the tube sheets which support the ceramic filter elements have been formed of metal. Attempts to use ceramic structural members to support the ceramic filter elements have not been altogether successful because of the fragile nature of traditional ceramics and the susceptibility thereof to corrosion when subjected to high temperature combustion gasses.
Nevertheless, ceramic structural members have an important advantage over metal structural members. Being of the same basic material as the filter elements with which they are used the structural members expand and contract simultaneously with the filter elements to reduce stress on the filter elements and to facilitate sealing of the filter elements to the structural support members.